Method of and apparatus for controlling the temperature of mammoth incubators



May 13, 1930. H. L. WATSON 1,758,017

METHOD OF AND APPARATUS FOR CONTROLLING THE TEMPERATURE OF MAMMOTHINCUBATORS 1925 3 Sheets-Sheet 1 Filed Feb. 11.

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Filed Feb. 11. 1925 3 Sheets-Sheet 5' Indentor: flar'oldjwai'son, Fj V7.f/ftorneys.

Patented May 13, 1930 UNITED STATES PATENT OFFICE HAROLD I]. WATSON, OFNEW BRUNSWICK, NEW JERSEY, ASSIG-NOR, BY MESNE AS- SIG-NMEN TS, TOAMERICAN IN CUBATORS, INC., OF NEW BRUNSWICK, NEW JERSEY,

A CORPORATION OF NEW YORK METHOD OF AND APPARATUS FOR CONTROLLING THETEMPERATURE OF MAMMOTH INCUBATORS Application filed February Myinvention is especially adaptable to that class of incubators, generallyknown as mammoth incubators, which embody a plurality of egg containingcompartments arranged in superposed tiers one above the other, andhaving heat radiating means extending through the several compartmentsin each tier connected with a suitable water heating unit from whichwarm water is supplied to heat the compartments.

It is requisite for the successful operation of incubators of thisgeneral class that the difierent compartments be maintained during mostof the hatching period at substantially uniform temperatures andconsiderable difficulty has been experienced in effecting this result byreason of the fact that when the heating water is drawn from a commonsource and thence conducted to the different superposed tiers thecompartments in the lower tiers are generally found to be cooler thanthose in the upper tiers.

In U. S. Letters Patent No. 1,508,569 granted to me August 5, 1924, andentitled Improvements in heating systems for mammoth incubators, Idisclosed and claimed a heating system comprising a heating unit forsupplying hot Water and piping extending therefrom to the radiatingmeans of each tier in such manner that the water for the upper tier istaken from a lower point in the common source than the water for thelower tier, with the result that relatively hotter water is continuouslysupplied to the latter than to the former to thereby compensate for thenormally cooler position in which the lower tier is disposed. While aheating system constructed in accordance with the disclosure of my saidapplication is entirely satisfactory in practical operation, it isobvious that, once installed, it is subsequently operative to alwaysdirect the hottest water to a given tier and relatively cooler water toother tiers although certain conditions often arise in the operation ofmammoth incubators under which it is desirable to selectively direct toa given tier, either continuously or for a short period only, relativelyhotter or colder water than would normally flow thereto yet withoutchanging the temperature of the water the other decks.

11, 1925. Serial No. 8,370.

flowing to the other tiers. Obviously such result cannot be effected byincreasing or decreasing the fire in the heating unit for by so doingthe temperature of the entire body of heating water is raised or loweredwith corresponding increase or decrease in temperature of the waterflowing to all of the units.

It is therefore an object of the present invention to provide a methodof selectively controlling the temperature of the compartments in thedifierent tiers or decks of mammoth incubators by directing hotter orcolder heating water drawn from a source coimnon to all of the decks,respectively, into each of them inaccordance with the degree oftemperature which it is desired to maintain in the compartments thereof,said method being capable of performance in such manner that thetemperature of the compartments in any given deckcan be controlledwithout affecting the temperature maintained in those of A furtherobject of my invention is the provision of apparatus for the performanceof the aforesaid method and which may be so operated as to selectivelydirect to a given deck of a mammoth incubator heating water ofrelatively higher or lower temperature than is being directed to otherdecks, the heating water for all of the decks being drawn from a sourcecommon to all of them and heated by a single heating unit.

My invention further includes all of the other objects, novel steps andmethods of operation and features of construction and arrangementhereinafter more particularly specified and described or which will beapparent from the accompanying drawings, in which I have illustratedvarious forms of apparatus constructed in accordance with the inventionand suitable for the performance of my improved method.

It will be understood that the invention may be utilized in connectionwith a mammoth incubator embodying any desired number of superposeddecks each of which is generally divided to form egg containing compartments, and each of which ordinarily embodies suitable heat radiatingmeans extending therein or therethrough, and I have therefore shown inthe said drawings only such portions of an incubator having three decksas is necessary for an adequate comprehension of the invention.

Referring now more particularly to the drawings, Fig. 1 is a front viewof one end of such an incubator in operative combination with one formof apparatus constructed in accordance with my invention; Fig. 2 is anenlarged side elevation of the heating unit and associated parts shownin Fig. 1, a portion of the wall of the unit being broken away to betterdisclose the arrangement of certain parts disposed therein, and Fig. 3is a front slevation thereof, partially in fragmentary section on line33 of Fig. 2. Fig. 4 is a fragmentary detail vertical section of certainof the parts of a slightly modified form of apparatus, while Fig. 5 afront elevation, subetantially similar to Fig. 1 save that certain partsare broken away in vertical section, illustrating a still furthermodified form of apparatus arranged for thermostatic as distinguishedfrom manual ope "ation. Like symbols are used to designate correspondingparts in the different figures.

The incubator as shown comprises three superposed decks or tiers A, Band C, although a greater or less number may be utilized, eachcontaining a plurality of compartmcnts having radiating means Rcomprising coils or pipes extending therethrough and connected, ashereinafter more particularly described, with a heating unit or furnaceH substantially of the construction usual to heaters of this charactersave in the particulars hereinafter referred to. This heater which isconveniently placed adjacent but spaced from one end of the decks may bepro vided with ash and fire doors D, D and with a smoke pipe S forcarrying away the products of combustion as well as with a water jacketJ substantially surrounding the inner fire pot K thereby providing achamber or space for containing the water to be heated. As heaters ofthis general class are well known and the construction of the variousparts to which reference has been made is thoroughly understood, furtherdescription thereof would be superfluous.

Suitable means are provided for controlling the fire in the heater,preferably by actuation of the doors D, D so as to maintain the water inthe jacket J at a predetermined substantially constant temperature, saidmeans in the form of the invention shown in Fig. 1 comprising anexpansion tank T supported at the upper end of a pipe E communicatingwith the interior of the jacket and containing a float F arranged toactuate a lever L pivotally supported adjacent the tank, the ends of thelever being connected by cords or chains G with the doors D, D in suchmanner that when the float is raised from a predetermined position byexpansion of the water in the system due to increase in temperaturethereof, the doors of the heater will be operated to reduce the rate ofcombustion therein, and vice versa when the float is lowered, thusmaintaining the water at a substantially constant temperature. Thismethod of controlling the heater and the means to which reference hasjust been made in connection therewith are convenient for accomplishingthe desired function but other means may be employed for that purposesuch, for example, as a thermal unit, as here inafter referred to inconnection with the form of invention shown in Fig. 5, or any othermeans suitable for so controlling the heater as to maintain the water ata substantially constant predetermined temperature.

In accordance with my invention the jacket wall of the heater isextended on one side, conveniently that intended to be placed adj acentthe end of the incubator, so as to form a water chamber 1 enclosed by avertical side wall 2, bottom wall 3, preferably horizontally disposedtop wall 4 and end walls 5-5, these several walls being preferably castintegral with the jacket wall, the chamber l being in free communicationwith the interior of the jacket and in effect forming an extensionthereof. It is from this chamber that the heating water is directed, inthe manner to be described, into the several radiators R, the chamberthus forming a common source from which all of the heating water for theincubator is drawn, and means are provided whereby the water for certainof the radiators or decks may be withdrawn from a higher or lower pointin the chamber in which, of course, the contained water becomesprogressively cooler as the bottom of the chamber is approached due tothe natural tendency of the hottest water to seek the upper part of thechamber.

For the purpose of conducting water from the heater to the radiator Rdisposed in the lower deck C and thence returning it to the heater afterit has circulated through the radiator, a pipe 6 may be carried from theupper part of the chamber 1, at which point the water is, of course, thehottest, to the radiator and a return pipe 7 carried to the lower partof the chamber to which it is connected through the medium of one of thenipples 8, the water thus passing to the radiator in deck 0 through pipe6 being of the same temperature as the water in the upper part of thejacket which is, as heretofore described, maintained at a substantiallyconstant predetermined temperature by suitable regulation of the fire inthe heater.

1n the form of apparatus to which particular reference is now beingmade, the independent and selective distribution of the water to theupper decks is effected through the medium of a plurality of verticallymovthe same.

able pipes which extend into the chamber and respectively communicatewith fixedly positioned pipes through which the heating water isconducted to certain of the decks, suitable means being provided foradjusting the movable pipes independently whereby their lower or inletends can be positioned at the same or at different vertical heightswithin the chamber so that the water flowing thereinto and thencepassing to the decks with which they communicate can be taken eitherfrom different levels or from the same level therein as may be desired.

As the construction and arrangement of each fixed and movable pipe andof the means for moving the latter are similar to each of the others, adescription of one of them together with its controlling means willsuffice and the following description will therefore be moreparticularly directed to the movable pipe and associated mechanism whichlies at the left hand side of the sheet in Fig. 2 and which may beoperated to control the temperature of the water flowing to deck A, thesame numerals, however, but with the addition of a prime being used torespectively designate corresponding parts which are operable to controlthe temperature of the water flowing to deck B.

Thus, for conducting the water to the radiator in deck A, a pipe 10 isarranged to extend from the inlet end of the radiator to a pointadjacent the upper part of the chamber 1, the pipe preferably passingthrough the wall 4 thereof to terminate a little below That part of thepipe adjacent the chamber is surrounded by and enclosed in a movablepipe or sleeve 11, the lower part of which extends into the chamber andterminates therein and the upper part of which extends above the wall4:. This movable pipe forms a snug but sliding fit on the pipe 10, andfor preventing leakage where the movable pipe passes through the wall asuitable stuffing box, conventionally represented at 12, may beprovided, and in a similar manner another stufling box 13 may bearranged at the upper end of the movable pipe to prevent leakage at thatpoint between it and the pipe 10. For returning the heating water to thelower part of the chamber 1 or other convenient part of the water spacewithin the heater a return pipe 14 is extended from the outlet end ofthe radiator R and connected into the wall 2 through one of the nipples8. Thus the heating water can free ly circulate upwardly in the conduitformed by the movable pipe 11 and the fixed outlet pipe 10, thencethrough the radiating coils and thence to the lower part of the chamber1 in the direction indicated by the arrows in Fig. 1, and it will beapparent that the temperature of the. water as it enters the lower endof the pipe 11 will be determined by the vertical height at which thatend of the pipe is disposed within the chamber.

For the purpose of raising and lowering the movable pipe 11 any suitablemeans may be employed, a convenient form thereof comprising a verticallyextending rack 18 having its upper end secured to a lug 19 fixed in anysuitable way adjacent the upper end of the pipe in such manner that therack will depend adjacent the wall 2 for cooperation with a pinion 20mounted on a shaft 21 journaled in a lug 22 carried by and convenientlycast integral with the acket J and a bracket 23 bolted to the face ofthe wall 2 the projecting end of the shaft adjacent the gear beingsquared to receive a removable hand crank 25 by means of which the shaftmay be rotated and the gear thereby caused to impart vertical movementto the rack so as to slide the movable pipe 11 up or down as may bedesired, the pipe 10, of course, remaining stationary during thisoperation as well as at all other times. For steadying the rack andholding it in alignment as well as for preventing rotation of themovable pipe which, should it occur, might throw the rack out ofengagement with the gear, the free end of the rack may be snugly butslidably extended through a suitable guide 26 secured to the wall 2 orother convenient point.

It will thus be apparent that by suitable operation of the crank themovable pipe 11 may be raised or lowered so as to bring its lower end toany desired point of vertical adjustment in the chamber 1 and that in asimilar manner the other movable pipe 11' may be similarly raised orlowered, the adjustment of either pipe being entirely inde pendent ofthe other. Thus, for example, both pipes may be set substantially asshown in Fig. 2 in which case the warmest water will be directed throughpipe 10, and somewhat cooler water through pipe 10, but any otheradjustment of the movable pipes may be made so that relatively hotter orcooler water will be selectively directed to either of the upper decksor water of the same temperature to all of the difierent decks, as maybe desired and in accordance with the degree of temperature which it isdesired to maintain therein.

In Fig. 4 I have indicated certain parts of a modified form of apparatusfor effecting the same result. In this apparatus instead of employing avertically movable pipe in association with each fixed outlet pipe, Iextend the fixed outlet pipe 10 through the top wall 4 of the auxiliarychamber and terminate the pipe a little short of the bottom wall 3thereof, the end of the pipe being preferably closed by a plug 30. Theportion of the pipe projecting below the top wall 4 is surrounded by apipe or sleeve 31 which extends through a stuffing box 32 carried by thewall 4 and is provided, exterior of the wall and at its upper extremity,with another stutfing box 33 to prevent leakage around the fixed pipe10. The lower end of the fixed pipe may be provided with an operativelyfixed-collar 34 to afford vertical support to the movable pipe whichlatter, to enable its convenient rotation, may be provided with a handle35 above the wall 4. F or determining the level at which the water fromthe chamber will be drawn, that part of pipe 10 enclosed by the movablepipe is provided with a plurality of vertically spaced slots or openings36 and the movable pipe with other openings or slots 37 horizontallyaligned therewith but preferably'so spaced circunrferentially of themovable pipe that when any slot 37 is in registry with any slot 36, allof the other slots in the movable and in the fixed pipe will be outofregistry with each other. Thus by rotating the movable pipe about thefixed pipe by means of the handle 35, registration can be effectedbetween slots at different vertical heights so as to admit water ofditierent temperatures to the fixed pipe which can then How tothe'particular deck with which such pipe is connected in the mannerhitherto described. It is believed that theoperation of this form ofapparatus will be readily comprehended without further description, itbeing of course understood that a movable pipe is employed in connectionwith each fixed pipe extending from the heater to the upper incuhaterdecks.

In the forms of apparatus hitherto described the adjustment of themovable pipes effected by manually operable means so that oncesaid meanshave been set to a given position the relative temperatures of the waterflowing to the different decks will remain constant irrespective of anyvariations in temperatureoccurring in one or more of the decks by reasonof some local condition or the like. Thus, for example, assuming themovable pipes to have been set by the operator in such manner as todirectsomewhat cooler water to the middle deck than is flowing to thelower deck and still cooler water to the upper deck and that a localcondition arises by which the air adjacent'the upper deck is suddenlymaterially lowered in temperature, it would of course be desirable topromptly direct relatively warmer water to that deck to compensate forthe eiiect of such local condition on the temperature inside the deck.This, with the forms of apparatus hitherto described, could be readilyaccomplished by the operator if he were aware of such local conditionbut in theabsence of the requisite manual adjustment'by him of themovable'pipe controlling that deck, the relatively cool water would, ofcourse, continue to flow thereto. Itmay thus be d'esirableincertain'types oi installations to provide'means for automaticallyadjusting the movable pipes in conformity with-fluctuations intemperature in the upper decks so as to obviate the necessity for manualadjustment thereof under'suchconditions, and I'shall therefore nowdescribe an apparatuscomprising means for that purpose and which isillustrated in Fig. of the accompanying drawings.

In this apparatus the decks A, B and C as Well as the heaterHmayconveniently be of form and arrangement similar to those alreadydescribed, theseveral decks being provid ed with'radia tors R, that inthe lower deck being connected directly with the upper part ofthechamberl of the heater by a pipe 6 and with thelower part of thechamber by a return pipe? so as to receive and return waterdirectly"fromand to thechamber. Instead of employingan expansion tankfor regulating the hea'ter'doorst-o control the fire as in the form ofthe invention hitherto described, I may, if desired, employ asuitablethermal unit U for this purpose, and such a uhit'is shown'disposed at asuitable point in the pipe- 6 and connected with the lower heater doorD. Obviously: however, the expansion tank method of control can be usedequally well in this form of theinvention or the thermal unit controlemployed in the form of the in vention" first described if desired andarranged to operate either one or both doors. for, as previously stated,the means utilized for controlling the rate of combustion of the fire inthe heater and in turn the temperature of the water in the'heater jacketmay be of any form suitable for the purpose.

For returning the water from the radiators in theupper decks I mayprovide suitable return pipes 40, 40 connected tothe lower part of thechamber 1 by nipples 8 similarly to the form of the invention hithertodescribed. while for conducting the heating water to the middle andupper decks I provide outlet pipes 42 which extend vertically upward,on'e tor each deck, from the upper wall 4 of the auxiliary chamber andto which they are connected by fixed nipples 43; from each of theseoutlet pipes a branch outlet pipe 44 extends to the inlet end of therespective radiators, being connected to the outlet pipe by a fitting orT 45. Slidably suspended within each outlet pipe so as to extend downinto the chamber 1 is a vertically movable pipe 46 whose upper end isconnected to a rod or wire 47 extending out of the upper end of theoutlet pipe, which is preferably left open for that purpose; this wire47 is connected to one end of a lever arm 49 either directly, or throughthe medium of an interposed link 48 as shown in connection with arm 49,which is pivoted on a bracket 50 carried by the adjacent deck andprovided with an adjustable counterweight 51 upon the opposite side ofthe bracket so as'to counterbalance the weight of the movable pipe andattached parts. For guiding and steadying the link 48 suitable guideslit) 52 may be disposed on the end of the deck A and the link extendedtherethrough.

Within each deck other than the lower deck and in a position tobereadily aifected by changes of temperature therein, a thermostat 55 ofany suitable form and construction is supported in any convenient mannerin association with a movable arm 56 connected by a link 57 with theadjacent lever 49 in such manner that the expansion and contraction ofthe thermally actuated elements of the thermostat in conformity withfluctuations in temperature in the deck are operative to swlng the leverabout its pivot and thus ralse or lower the movable pipe 46 so as tomove its lower or inlet end to a higher or lower position in the chamberwith consequent regulation of the temperature of the water flowingtherethrough to that particular deck. Thus, upon an increase oftemperature in any deck, the thermostat therein will automaticallyexpand and thereby lower the movable pipe so as to direct cooler waterinto the deck until the temperature therein is brought back to normalwith corresponding actuation of the thermostat to again raise the pipeto the position to which it was initially adjusted and, correspondingly,upon a decrease of temperature in the deck the movable pipe controllingit will, through the operation of the thermostat, be raised to directhotter water into the deck until normal conditions are again restored.It will of course be obvious that, if desired, means of any suitablecharacter may be provided for shortening or lengthening the wires orrods 47 so as to permit the movable pipes to be initially adjusted toany desired height.

While I have herein described'and illustrated with some particularitycertain forms of apparatus comprehended by and constructed in accordancewith my invention and well adapted for the performance of my improvedmethod for controlling the temperature of mammoth incubators, I do notthereby desire or intend to limit myself solely to the employment ofsuch apparatus for the performance thereof nor to any specific form,construction or arrangement of the various elements entering into suchapparatus as the same may be modified or varied from the preciseembodiments and forms to which reference has herein been made withoutdeparting from the spirit and scope of the invention as defined in theappended claims.

Having thus described my invention, I claim and desire to protect byLetters Patent of the United States:

1. The methodlof controlling the temperature in different decks of amammoth incubator which consists in selectively directing hotter orcolder heating water from a common source into each of said decksupon adecrease or increase of the temperature therein.

2. The method of maintaining substantially constant predeterminedtemperatures in different decks of a mammoth incubator which consists incausing the heating water for the different decks to flow thereinto fromhigher'or lower point in a common reservoir from which all of said wateris drawn to thereby compensate for fluctuations in the respectivetemperatures in the different decks.

3. The method of controlling the respective temperatures in difi'erentdecks of a mammoth incubator which consists in selectively directingheating water from different levels in a common reservoir into therespective decks, said levels being determined in conformity with thetemperature it is desired to maintain in each deck.

4. The method of controlling the respective temperatures in differentdecks of a mammoth incubator which consists in selectively varying thelevels in a common reser-' voir from which the heating water isconducted to the respective decks in conformity with the temperature itis desired to maintain in each deck.

5. The method of controlling the respective temperatures in differentdecks of a mammoth incubator which comprises the steps of selectivelydirecting heating water from a common source to the different decks andvarying the levels from which the water is drawn from said source toselectively regulate the temperatures within the different comprisingegg containing compartments and radiating means therein, of a waterheating unit, a conduit extending from the unit to one of said radiatingmeans'and comprising a stationary pipe and a pipe movable with respectthereto and extending into said unit and a return conduit extending fromthe radiating means to the water heating unit.

8. The combination with a mammoth incubator having a plurality ofseparate decks comprising egg containing compartments and radiatingmeans therein, of a water heating unit, a conduit extending from theunit to one of said radiating means, separate conduits ext-ending fromsaid unit to each of the other radiating means, each comprising astationary pipe and a movable pipe xtending into the unit, means foreffecting movement of each of said movable p pes independently wherebythe heating water can be seand radiating-means therein, of a waterheater having a water heating chamber, a conduit extending from saidchamber to one of said radiating means, and a separate conduit extendingfrom said chamber toanother o t'isaid radiating means and comprising astationary pipe and a movablepipe communicating therewith projectinginto :the chamber and having an (opening within the chamber throughwhich water can flow into the pipe, means tor moving the movable pipe soas to vary the position ,of said opening in the ch amber and returnconduits extending from said radiating means to the water heater.

10. The combination with a mammoth incubator having a plurality ofseparate decks comprising .egg containing compartments and radiatingmeans therein, or a water heater having a water heating chamber, aconduit extending from saidlchamber to one of said radiating means, andconduits extending from said chamber to each of the other of Saidradiating means, each of said last mentioned conduits comprising a fixedpipe and a movable pipe communicating therewith, projecting into thechamber vand having an opening within the chamber through which watercan flow into the pipe, means for independently positioning each movablepipe so asto permit the heating water to flow thereinto and thence toits communicating fixed pipe from a higher or lower level in the chamberand return'conduits extending from saidradiating means to the waterheater.

11. The combination with a mammoth incubator comprising a plurality ofseparate superposed decks each having radiating means therein, of awater heating unit having a water chamber, and separate conduits forconducting heating \vater from the chamber to eachogf said radiatingmeans, said conduits for each of the upper decks comprising a movablepipe extending from within the chamber and a fixed pipeextending fromthe movable pipe to the radiating means, means for. effecting.vertical-adjustment of the movable pipe whereby the lower .end thereofmay bewdi spiosed at a hig er .orlower point within he hamber nd returnconduits extending from saidradiatingmeans. to the water heat ing unit,

12,-- The comb nat on wit a mammoth incubator comprising, a plurality ofseparate decks each having radiating means therein, of a water heatingunit having a water chamber forming a common water heating source forall of said radiating means, means for selectively determining the pointin said chamber from which the heating water for certain of theradiating means will respectively be drawn, said means comprising aseparate fixed pipe extending from each radiating means and a movablepipe communicating therewith and extending into the heating chamber andhaving an inlet disposed therein, and means for adjusting each movablepipe independently of each of the other movable pipes so as to vary theposition of its inlet with respect to the chamber, and return conduitsextending from the radiating'means to the water heating unit.

13. The combination with a mammoth incubator comprising a plurality ofseparate decks each having radiating means therein, ofa water heatingunit having a water chamber forming a common water heating source forall of said radiating means, means for selectively determining the pointin said chamber from which the heating water for certain of saidradiating means will be drawn comprising a separate conduit extendingfrom the chamber to each of said radiating means and embodying pipes,one of which is vertically movable with respect to another,communicating therewith and having its lower end disposed within thechamber, means for efi'ecting vertical adjustment of each movable pipeindependently, and return conduits extending from the radiating means tothe water heating unit.

14. The combination with a mammoth incubator comprising a plurality ofseparate decks each having radiating means therein, of a water heatingunit having a water chamber forming a common water heating source forall of said radiating means, means for selectively determining the levelin said chamber from which the heating water for some of said radiatingmeans will be drawn, said means for each of said radiating meanscomprising a separate conduit formed of relatively movable telescopicpipes one of which has its lower end disposed within the chamber and isvertically movable with respect thereto, means comprising a rack andpinion cooperative with said vertically movable pipe-for adjustablycontrolling the position thereof with respect to the chamber, and returnconduits extending from the radiating means to the water heating unit.

15. The combination with a mammoth incubator comprising a plurality ofseparate decks each havingradiating means therein, of a water heatingunit having a water chamber forming a common water heating source forall of said radiating means, means for selectively determining the levelin said chamber from which the heating water for some of the radiatingmeans will be drawn and comprising for each of said radiating means aseparate conduit formed of relatively movable pipes arranged totelescope one within the other, one of said pipes being movable withrespect to the chamber and hav ing its lower end disposed therein, meanscomprising a rack carried by each movable pipe and a gear cooperativewith the rack for raising and lowering the pipe so as to vary the heightof its lower end with respect to the chamber, and return conduitsextending from the radiating means to the water heating unit. o Inwitness whereof, I have hereunto set my hand this 7th day of February,1925.

HAROLD L. WATSON.

